Diffraction angle prediction of surface micromachined planar curved grating and crossed grating

In this study, the different curvature of surface micromachined planar curved grating is systematically investigated. The crossed grating with various pitches was also explored. The planar curved grating and crossed grating were fabricated using multi-user MEMS processes (MUMPs) provided by MEMSCAP Inc. The angular separation and the number of diffracted orders were found. Experimental indicates that the diffraction patterns and curvature of planar curved grating reveal a close relationship. As curvature of planar curved grating increases, the vertical diffraction angle increases, resulting in a strip patterns of the planar curved grating. When the pitch of crossed grating increased, diffraction angle decreases. The proposed gratings can be applied to optical measurement and micro-optics applications.